gc compiler error: confusing error messages for unused constant expression

[ianlancetaylor]

This is a variant of issue #1722 aka bug337.go

cat > foo.go << _EOF_
package main

import "unsafe"

func main() {
    unsafe.Alignof(0)
}
_EOF_
6g foo.go
foo.go:6: 4 not used

The error message should say Alignof(0), or "function call", or many other
things, but definitely not "4".

[lvdlvd]

Comment 1:

Labels changed: added compilerbug.

Owner changed to @lvdlvd.

[rsc]

Comment 2:

This issue was closed by revision 4349eff.

Status changed to Fixed.